Smallpox

Definition

Smallpox is a viral infection. It is contagious and can be deadly. The disease was eliminated worldwide. This was done through global immunization programs. The last known natural occurring human case was in 1977. Governments have studied its use as a germ-warfare weapon. As a weapon, it would be released in the air. Those exposed could develop the disease. They would then pass it to other people.

Rash appears on the mouth, throat, face, and arms, then spreads to the legs and trunk

Red, flat lesions

Lesions appear at the same time

Lesions fill with fluid, then pus

Crusts form during the second week

Scabs form and fall off after 3-4 weeks

Hemorrhagic symptoms include:

High fever

Fatigue

Headache

Backache

Possible stomach pain

Dark red coloration

Bleeding into the skin and mucus membranes

Malignant symptoms include:

High fever

Fatigue

Headache

Backache

Slowly developing lesions that remain soft and flat

Skin looks like reddish-colored crepe rubber

Large amounts of skin may peel, if the person with smallpox survives

Diagnosis

You will be asked about your symptoms and medical history. A possible source of exposure will be looked for. A physical exam will be done.

Test may include:

Examination of saliva and fluid from skin lesions under a microscope

Taking a sample (a culture) of saliva and fluid from skin lesions

Blood test to detect antibodies to smallpox

Treatment

No effective treatment for smallpox currently exists. Doctors can offer supportive care. Steps will be taken to prevent the spread to others.

Supportive Care

Fluids are given. The skin is kept clean. Medications can help control fever and pain. Antibiotics do not work against viruses. They may be given if other infections develop.

Public Health Measures

Cases are reported to public health officials. A person infected with smallpox should be kept isolated. This will help prevent the spread of infection.

In most cases, family members would provide care at home. Caregivers should:

Be vaccinated

Wear a mask, gloves, goggles, and a gown

Disinfect clothing, bed linens, and surfaces

People in the hospital will be placed in a special room. In some cases, forced quarantine may be necessary.

Prevention

Many people were immunized prior to 1972. That protection has likely worn off or decreased. Routine
vaccination
is not recommended in the United States.

An emergency supply of the vaccine is kept. A vaccination within 4 days of exposure may prevent the disease. It can also make symptoms less severe. Anyone in close contact with someone who is infected after the fever has started should receive the vaccine. Medical and emergency personnel also should be given the vaccine.

Two weeks or more could elapse before the first symptoms occur. The success of an attack would depend on the dose that was inhaled. Experts predict most of the released viruses could live in dry, cool air, without sunlight, for up to a day. Each person infected would likely pass the disease to 10 to 20 other people. Those people, in turn, could spread it to others. The fatality rate in naturally occurring smallpox is 30% or higher.

Revision Information

This content is reviewed regularly and is updated when new and relevant evidence is made available. This information is neither intended nor implied to be a substitute for professional medical advice. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with questions regarding a medical condition.

Smallpox. University of Minnesota Center for Infectious Disease Research and Policy website. Available at: http://www.cidrap.umn.edu/infectious-disease-topics/smallpox. Updated February 24, 2014. Accessed January 16, 2015.